Meeting SDK (Windows): Joining a webinar created inside a Zoom Events Hub. Supported path or known limitation?

Meeting SDK
1

Meeting SDK Type and Version
Meeting SDK for Windows 7.0.5 (C++)

Description
I join webinars via the Windows Meeting SDK using SDK_UT_WITHOUT_LOGIN with a user ZAK. Webinars created directly in Zoom join correctly for host, panelist, and attendee. Webinars created inside a Zoom Events Hub fail to join at every stage (practice session and live).

The hub’s join link is of the form https: //events .zoom.us/ejl/ (I added spaces as links are not allowed here) there is no meeting number in it and no tk= parameter, so it isn’t something JoinParam can consume. I located the underlying webinar ID via the link’s browser redirect and passed that number to the SDK directly.

Error

  • Underlying webinar number → SDK to JoinParam → MEETING_STATUS_FAILED with result 65535 (MEETING_FAIL_UNKNOWN).
  • Sanity check: pasting the same bare number into the Zoom Workplace desktop client’s Join box returns “Unable to Join Zoom event… please register from the event page or join from your unique join link,” Error code 13218.

So Zoom’s own desktop client also refuses the bare number and requires the event-join link.

Troubleshooting routes taken

  • Regular (non-hub) webinars join correctly for all roles, so the auth / ZAK / JoinParam wiring is sound.
  • Per Zoom’s developer blog, webinarId/meetingId are distinct entities from eventId/sessionId, and Events join/registration run through Events-specific flows.
  • The underlying webinar number is valid: the events link redirects to it and the desktop client joins through the event flow.
  • JoinParam4WithoutLogin exposes meetingNumber, vanityID, psw, userZAK, and webinarToken (tk). None of these carries an event-join token, and the ejl link has no tk to extract.

Question
Is there any supported Meeting SDK path to join a webinar hosted inside a Zoom Events Hub, a token field I’m missing, an OBF/ZAK variant, or a documented join flow for Events sessions? Or is joining Events-hosted sessions via the Meeting SDK a known unsupported scenario? If unsupported, is support planned?

2

I would not treat the bare underlying webinar number as the supported join path for Zoom Events. Zoom Events sessions have their own event/session model, and Zoom explicitly separates eventId / sessionId from regular webinarId / meetingId in its Zoom Events registration flow. That matches the desktop client behavior you saw with 13218.

The path I’d test is: get the Events session token using GET /zoom_events/events/{eventId}/sessions/{sessionId}/join_token, then pass that value into the Windows Meeting SDK JoinParam4WithoutLogin.join_token field. Keep using the underlying webinar or meeting number as meetingNumber, but don’t rely on it by itself. webinarToken is a separate field for normal webinar tk flows, and it doesn’t look equivalent to the Events session join token.

Two quick checks: confirm your 7.0.5 headers expose join_token on JoinParam4WithoutLogin, since older examples often omit it. Confirm the Events API returns code: 0 and a non-empty token for the same attendee/ticket/session before calling Join.

For production meeting capture workflows, Recall’s Meeting Bot API can be a simpler integration path.